U.S. Pat. No. 675,418 A discloses a rotary conveyor having a drum-shaped shell with fingers extending through openings in the shell. The fingers are mounted and can rotate on an eccentric, fixed axle, so that the length by which the fingers project out of the shell depends on the rotation position of the rotating shell which carries the fingers along with it as it turns. On the axle, four groups of fingers are arranged axially alongside one another, each group having three fingers, one of which in each case passes through one of three openings distributed around the circumference of the shell at an offset of 120° from the others. The fingers of each group are separately pivoted on the axle, and for this U-shaped sheet components with holes through which the axle passes are provided.
A similar rotary conveyor is disclosed in GB 612 962 A. Several fingers in one group are pivotally mounted on collars, except for one finger which is solidly attached so as to carry the collar around as the shell rotates. The remaining fingers are hinged to the collar so that they can swivel separately.
GB 1 151 119 A discloses a rotary conveyor, in which pairs of adjacent fingers are attached to a sleeve and the holders are pushed onto and can rotate around the eccentric axle.
DE 2 103 981 A discloses a rotary conveyor arranged over the straw walkers of a combine harvester to improve the separation of residual grains from the threshed crop, in which elastic prongs are guided on a curved track.
DE 31 11 177 A describes a rotary conveyor with two diametrically opposed groups of fingers. The fingers are arranged on axially orientated crossbars, which can swivel about an axle displaced from the fingers in the rotation direction and orientated parallel to the longitudinal axis of the rotary conveyor. The angular position of the crossbars is controlled by connecting rods connected to a fixed axle.
For conveying harvested crops, under certain circumstances it is desirable to have drum conveyors with as many fingers as possible, for example in the middle of transversely extending augers of harvesting platforms or in conveyors positioned above the straw walkers of combine harvesters. When the holders of the fingers are arranged next to one another in the axial direction on the eccentric axle, as in the case of GB 1 151 119 A, the number of fingers is limited by the width of the holders. The arrangement disclosed in U.S. Pat. No. 675,418 A allows a larger number of fingers, but has the disadvantage that replacement of a holder that has become defective entails dismantling the conveyor completely, which is a very time-consuming and therefore expensive process. In GB 612 962 A fingers are also arranged in a star, but almost every finger is associated with its own rotating attachment to the holder also fitted onto and pivoting around the axle, which results in a relatively expensive structure. The curved track to control prongs disclosed in DE 2 103 981 A and the control via connecting rods proposed in DE 32 11 177 A are, in contrast, essentially of a more complex design than when the fingers are fitted to an eccentric shaft.